I have a Scarlett 18i8 interface (pretty common and popular), and I have my mics setup correctly. The audio is good . . . viewers said the fidelity was great but that the volume was low, Some viewers had powered speaker systems and could simply turn it up, but others were viewing using laptop speakers or a iPhone or Android. Those viewers complained the volume was too low - lower than the typical YouTube video. Is there something I can do to fix it? I have my interface turned all the way up.
In addition to the volume on the external interface, you can also try increasing the audio input levels on your computer.